Just 4 teaspoons of olive oil a day can help your heart

Even a small daily dose of olive oil can reduce your risk of heart disease, says new research.

We all know the benefits of the Mediterranean diet, but sometimes its hard to swap hot buttery toast for a healthy tomato or chickpea salad. So you may be happy to hear that scientists have managed to prove conclusively for the first time that having a small daily portion of olive oil can improve heart health on its own, without a single chickpea or aubergine.

Metabolic health researcher Dr Bill Mullen, from Glasgow University, discovered that just 20ml (4tsp) a day of raw (uncooked) olive oil can reduce biomarkers for heart disease within six weeks.

“In 25 years of nutritional research, I have never seen results as statistically significant and as clear,” he says. “You can tell someone to eat an apple a day all you like, but you can’t prove the effect of that apple. Now we can say for certain that olive oil has a measurable effect.”

A jug of olive oil being poured into a glass bowl with olives dotted aroundCredit: Shutterstock /Dusan Zidar

Olive oil can protect against heart disease

Reduce your risk of heart disease in six weeks

Mullen’s study took volunteers from Glasgow, an area with a traditionally low intake of olive oil and a high incidence of heart disease.

They were given either a daily 20ml of standard olive oil or extra virgin olive oil as a drink (they didn’t know which), then their urine was measured. Samples were taken in 2013 but it was only recently that Mullen was able to use a new kind of test known as a ‘multi-peptide biomarker’ to search for certain protein fragments in the urine linked to poor heart health – a kind of fingerprint for heart disease.

A reading above zero meant you had heart disease (+1 was the worst); a reading of -1 meant very healthy, with no heart disease present. Both kinds of oil produced a positive change in the readings from week three, and it was still improving at week six when it reached 0.3.

Even a little olive oil makes a difference

Perhaps thankfully, you don’t have to drink it to get the benefits.

“It’s really easy to get 20ml a day,” says Mullen. “You can use it in salad dressings and drizzle it on all kinds of things. As a wee starter I have a little bowl of olive oil with some balsamic vinegar and dip my bread into it. It’s so simple.”

“Or just eat olives – four or five may give you 4.4ml of oil. Instead of using butter, I pierce my warm toast with a fork and drizzle olive oil over so it soaks in.”

And even if you don’t consume it every day, it will still be advantageous to your health if, in the long term, you have more days of olive oil intake than not.

Olive oil appears to be better than other oils

Other oils, like rapeseed and sunflower, don’t appear to have the same effect on heart health, though Mullen tested those on different volunteers in a separate study, so comparison is unfair.

Why olive oil is good for your health

What’s the ‘magic’ in olive oil?

Scientists aren’t sure if it’s one nutrient, or the fact you tend to use it in place of less healthy fats.

“It’s really difficult to know, which is why we need more research,” says Mullen, who conducted this latest test using funding from Italian olive oil producers Filippo Berio, though he has been working on oils for 12 years using a variety of funding.

Olive oil is what’s called a monounsaturated oil, the kind also found in nuts and avocados. It contains predominantly monounsaturated fatty acids such as oleic acid, which have an anti-inflammatory effect. It also contains a little saturated fat (14%) and polyunsaturated fat (11%).


Olive oil also contains Vitamin E

Some studies have found olive oil lowers levels of ‘bad’ LDL cholesterol that builds up as plaque deposits in your blood vessel walls and narrows them.

“Olive oil in your diet can also increase HDL, which is protective against heart disease,” says dietitian Priya Tew.

It also contains vitamin E (1 tbsp or 14g has 1.9mg – around half your daily amount – says the NHS), which is a powerful antioxidant and good for heart and eye health, plus vitamin K (1 tbsp or 14g has 8mcg, around 10% of your daily amount). This plays a role in blood clotting and bone health.

Extra virgin olive oil – the purest kind that’s pressed from ripe olives without heat – also has high levels of polyphenols, antioxidants that protect cells from damage and reduce your risk of many chronic diseases.

Extra virgin olive oil has bigger health benefits

Do I need to use extra virgin oil?

It doesn’t seem so based on this study. Both groups enjoyed the same benefits to heart health. And there were fewer dropouts in the standard olive oil group, probably because of its milder taste.

However, most studies do show that extra virgin oil has greater health benefits as it is less refined so retains powerful plant chemicals.

“In all the big population studies, extra virgin olive oils always come out better over 20 or 30 years, probably because they contain polyphenolic compounds that act as antioxidants in the body,” says Dr Mullen.

Generally, the more expensive the olive oil, the less processed it is, and hence the higher concentration of polyphenols it has. In a study at the University of Granada, researchers showed that frying vegetables gently in extra virgin olive oil increased their antioxidant capacity and was healthier than cooking them in water.

Don't use extra virgin olive oil for frying

If you’re frying something at high heat – such as steak – it’s best not to use extra virgin oil.

Heat destroys the polyphenols so you’re wasting your money, and it has a lower smoke point than normal olive oil, so it could release harmful compounds, says Prof Martin Grootveld at De Montfort University, Leicester.

Olive oil can reduce the risk of cognitive decline

Olive oil helps protect against memory loss

Anything that’s good for your heart is also good for your brain as it keeps blood vessels healthy and preserves blood flow, including to your head. This in turn reduces the risk of cognitive decline, and this may be why studies have consistently found low rates of dementia in cultures that consume a lot of olive oil.

In fact, a huge population study in the US published in 2022, analysing the diet of 90,000 people over 28 years, found those with the highest olive oil intake – more than half a tablespoon a day (7.8ml) – had a 29% lower risk of dying from neurogenerative diseases like dementia. They had a 19% lower risk of dying from cardiovascular disease, 18% less chance of dying from respiratory disease and a 17% lower risk of dying from cancer.

Even one teaspoon of olive oil a day was associated with a 12% reduced risk of death from all causes.

Can olive oil reverse heart disease?

What if I already have heart disease?

“Once the plaque is there in your arteries it’s there, you can’t move it,” says Mullen.

“You can control it with drugs, but you can’t cure it. That’s why the whole basis of our study was to pick up biomarkers of heart disease before it got to a bad state in 20 years. However, if you change your diet, you could stop it getting worse.”

Olive oil benefits our skin too

Abigail Roberts, Sports Nutritionist at Bulk.com says olive oil is packed with antioxidant compounds, like vitamin E, oleacein, and oleocanthal. As well as compounds called polyphenols, which are phenomenal for hair, skin, joints, and weight.

“It is also rich in antioxidants and skin-friendly lipids that can help address skin concerns like dryness or rough-feeling skin.

“While many people will spend a fair amount of money on skin creams and hair masks, they tend to forget about their diet. What we put inside our bodies is just as important as what we put on the outside.”


Written by Rachel Carlyle